In an image recording apparatus for recording a medical image using a heat storage fluorescent sheet, e.g., a digital radiographic system, CT, MR, etc., a wet system in which an image is photographed or recorded on a silver salt photographic light-sensitive material, and then wet processed to obtain a reproduced image, has been used.
However, in recent years, a recording apparatus by a dry system in which wet processing is not necessary to be carried out has attracted public attention. In such a recording apparatus, a light-sensitive and/or a heat-sensitive recording material (a light-sensitive heat-sensitive recording material) and a heat-developable light-sensitive film (hereinafter referred to as "a recording material") are used. In this recording apparatus by a dry system, a latent image is formed by irradiation of a laser beam (scanning) on a recording material at exposing part, then the recording material is heat developed by contacting with a heating means such as a heating drum at heat developing part, thereafter the recording material on which an image has been formed is discharged from the recording apparatus.
By such a dry system, not only image formation can be effected within a short period of time as compared with wet processing but also a problem of the disposal of a waste water in wet processing can be resolved, therefore, the increase of demand for such a system in the future is predictable enough.
In the above-mentioned dry system, high image quality is required particularly for medical images, so that recording materials higher in sensitivity are used. Accordingly, slight fluctuations in developing temperature causes great deterioration of image quality.
Now, development is usually performed at a high temperature of about 120.degree. C., so that heat given in the development remains in the recording materials even after peeled off from the heating means. Further, it is known that development proceeds even at a temperature of about 90.degree. C., although it depends on the kind of recording material. The recording materials immediately after peeled off from the heating means have a temperature within this development proceeding temperature range.
On the other hand, in heat developing apparatuses of this kind, peeling claws for securely peeling off the recording materials from the heating means are usually provided in close proximity to the heating means. When the recording materials still having a temperature within the development proceeding temperature range immediately after peeling off from the heating means come into contact with the peeling claws, differences in heat conduction between contact portions and other portions are developed, resulting in appearance of image defects on the contact portions.